CVE-2021-33224: Malicious File Upload

Published Feb 24, 2023
·
Updated

File upload vulnerability in Umbraco Forms v.8.7.0 allows unauthenticated attackers to execute arbitrary code via a crafted web.config and asp file.

Affected Software

1 affected component
Umbraco Umbraco Forms=8.7.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Compensating control

    Restrict Umbraco Forms upload endpoints and any related file upload functionality to authenticated users only, to prevent unauthenticated exploitation (crafted web.config/asp).

  2. Operational

    Scan Umbraco site directories for any uploaded or dropped web.config/ASP webshell artifacts created via the crafted web.config and asp technique, and remove any malicious files found.

Event History

Feb 24, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-33224?

The severity of CVE-2021-33224 is critical with a score of 9.8.

2

How does the vulnerability in Umbraco Forms v.8.7.0 affect the software?

The vulnerability affects Umbraco Forms v.8.7.0.

3

What is the vulnerability in Umbraco Forms v.8.7.0?

The vulnerability in Umbraco Forms v.8.7.0 is a file upload vulnerability that allows unauthenticated attackers to execute arbitrary code via a crafted web.config and asp file.

4

How can unauthenticated attackers exploit CVE-2021-33224?

Unauthenticated attackers can exploit CVE-2021-33224 by uploading a crafted web.config and asp file.

5

Are there any references available for CVE-2021-33224?

Yes, there are references available for CVE-2021-33224. You can find them at http://umbraco.com and https://our.umbraco.com/packages/developer-tools/umbraco-forms.

Contact

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